1. Field
This invention relates to a turbocharged compression ignition engine. More particularly, the invention relates to components for a turbocharged compression ignition engine and to a compression ignition engine including such components.
2. General Background
Mining environments are clearly hazardous environments where extreme safety precautions must always be considered and upgraded. Of particular importance, are the safety measures designed with regard to the combustibility of the material being mined. Any object brought into a mine can either create a spark or simply heat up to temperatures above a critical ignition temperature which can cause explosions. This is a serious problem within coal mines, in particular, since coal dust can spontaneously ignite at temperatures of about 160° C. to 170° C. This means that any object introduced into the mines must not emit flames or sparks and surfaces must remain well below critical temperatures.
Heavy machinery is used throughout the mining industry to move materials around the mines, in particular LHD (Load Haul Dump) machines. These machines require a great deal of power to move heavy loads. Ideally turbocharged engines should be used since they increase the amount of power in comparison with a naturally aspirated engine of similar capacity without suffering a significant fuel consumption disadvantage.
However, turbochargers of compression ignition engines have surface temperatures in excess of 150□C and as a result temporary measures have been implemented on and around ‘hot spots’ to reduce the surface temperature of the turbochargers and increase safety measures. As a consequence of the unreliable nature of this temporary method, non-turbocharged engines have been traditionally used since their surface temperatures remain below the critical temperatures, although they continue to remain inefficient in light of the present technology.
In addition to the problems associated with the surface temperatures of the turbocharger, flames or sparks emitted from the engines or occurring within the engine itself, also present a potential danger. As a result, flame traps are positioned within the engine system to arrest the transmission of flames.
At present, the arrangement is such that the flame traps are situated at the inlet of the turbocharger so that the aftercooler is situated directly off the turbocharger at a right angle. This arrangement does not optimise the space constraints within the engine and furthermore the arrangement of the flame trap, turbocharger and aftercooler do not optimise fluid flow rates within the system. Thus there is a need for improved methods to increase the efficiency and safety of the turbocharged compression ignition engine.